The following conditions must be met to renew a personal certificate in accordance with these instructions:

1. You have a valid personal certificate issued by CESNET CA4 and you have the appropriate private key. If this is not the case, it is necessary to partially repeat the registration process.
2. The new certificate should have the same content as the existing certificate. If you require a certificate with a different content, follow the instructions in Changing the certificate content.

Reply to this email. Usually, just press the Reply in your mail client and send the mail. Make sure that you have signed your email with your CESNET CA 4 certificate and that the original notification text, or at least the serial number line, has been retained in your reply:

...
and Serial Number: XX: XX: XX: XX: ...
...

Send a signed email to prolonger@cesnet-ca.cz containing a certificate renewal request with the text:

Requesting renewal of personal certificate
with serial number: XX: XX: XX: XX: ...

The serial number must be in hexadecimal format with colons (see How to find the serial number of the certificate). Make sure you have signed your email with your CESNET CA4 certificate.

The automat verifies your signature and sends you activation data for the certificate generator.